The present invention relates to an optical connector element having a one-piece body.
It is known that an optical fiber includes a core which is the portion in which a light beam to be transmitted propagates, and that the core has a centering tolerance of about 0.8 .mu.m (for single mode fibers) within the section of the fiber.
It is also known that an optical fiber is mounted in a connector element by being fixed in a sheath referred to as a "ferrule", in which sheath the fiber is generally glued and then polished at its end, and that such mounting induces a centering tolerance of about 2 .mu.m.
As a result, the position of the core of an optical fiber relative to its ferrule is subjected to a cumulative tolerance value which, when two fibers are to be connected together poses a problem because there is a high likelihood that the facing cores of the two fibers will not coincide.
To reduce this risk of non-coincidence, it is known that it is possible to perform a standardized angular positioning operation in the following manner, once the fiber has been set in resin in its ferrule, and its end has been polished.
The fiber held in the ferrule is presented to the end of a fiber mounted in an orientation plug. In the plug, the fiber has standardized eccentricity, i.e. its core is offset relative to the geometrical center of the outside section of the ferrule of the plug by a given distance in a given direction.
The ferrule is presented in a plurality of different angular positions facing the orientation plug. In general, four or six such positions are used which are angularly spaced apart by 90.degree. or by 60.degree..
A light signal is transmitted between the fiber to be oriented and the fiber in the orientation plug, and the angular position in which the signal is transmitted best is chosen as being the optimum orientation.
The ferrule is then held stationary in a connector element in an angular position in which the fiber lies in its optimum orientation, by means for preventing it from rotating, which means are provided in the connector element.
Thus, when the fiber oriented in this way is connected to another fiber oriented under the same conditions, the cores of both of the facing fibers lie within the same angular sector.
It is also known that, in order for two coupled-together connector elements to guarantee good optical connection between two fibers, it is essential for the end faces of the two fibers to be held facing each other independently of the mechanical stresses to which the coupled-together connector elements might b subjected, which stresses can, in particular, result from handling one or more optical cables.
For that purpose, an alignment sleeve is used for the ferrules, and the inside of each connector element is organized to allow clearance between firstly the fiber and its ferrule and secondly the remainder of the connector element, so that the two ferrules held facing each other by the alignment sleeve inside the two coupled-together connector elements form an assembly which is capable of floating inside the coupled-together bodies of the two connector elements.
One difficulty with the optical connector elements lies in the need to hold the ferrules angularly while also allowing them to float inside each connector element.